Leica M205 C, M205 A, M165 C manual TL RC / TL RCI Operation, Setting the relief contrast

TL RC™ / TL RCI™: Operation

Setting the relief contrast

The two switches on the left side of the trans- mitted-light base TL RC™/TL RCI™ activate two built-in flaps. The outer switch (1) controls the inverted relief contrast, and the inner switch (2) adjusts the positive relief contrast.

Depending on the flap position, a part of the opening of the built-in Fresnel lenses are covered, which results in the different contrast effects. Phase structures typically act as spatial, relief-type images—in the positive relief contrast like hills, in the inverted relief contrast like valleys.

Increased contrast without relief is attained if both diaphragms are set to 45°. A gap-like illuminated area is created. By tilting the deflec- tion mirror slightly, you can move the gap over the entire field of view and quickly toggle between positive and negative relief images. The dynamic effect makes it easy to distinguish phase structures from amplitude structures.

1 2 3

1Switch for adjusting the inverted relief contrast

2Switch for adjusting the positive relief contrast

3Deflection mirror

Leica M series Manual 83